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Showing 1 to 20 of 66 for “"Turbofan Engine"”.
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Description of a turbofan engine product development process
… are necessary for the development of a turbofan engine and how they evolve through the product development cycle. This work utilizes a parameter-based design structure matrix (DSM) to define the interfaces and interdependencies present in a large commercial aircraft propulsion system. …
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Turbofan engine sizing and tradeoff analysis via signomial programming/
This thesis presents a full 1D core+fan flowpath turbofan optimization model, based on first principles, and meant to be used during aircraft conceptual design optimization. The model is formulated as a signomial program, which is a type of optimization problem that can be solved locally using …
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Influence of Turbofan Engine Design Parameters on Aircraft Environmental Impact
… carriers and propulsion systems architectures, turbofan engines power the majority of commercial aircraft. Therefore, aviation’s environmental impacts are significantly influenced by the design of these turbofan engines. Hence, we should drive the design of modern turbofan engines, informed with …
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Effect of BLI-Type Inlet Distortion on Turbofan Engine Performance
… layer flow through a serpentine inlet into a turbofan engine adversely affects the performance of the engine. The available literature has only yielded studies of the effects of this specific type of inlet distortion on engine performance in the form of numerical simulations. This work seeks …
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Data-Driven Modeling of Tracked Order Vibration in Turbofan Engine
Aircraft engines are one of the most heavily instrumented parts of an aircraft, and the data from various types of instrumentation across these engines are continuously monitored both offline and online for potential anomalies. Vibration monitoring in aircraft engines is traditionally performed …
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Fluid Dynamics of Inlet Swirl Distortions for Turbofan Engine Research
… development of aircraft is aimed at improving engine efficiency, while reducing fuel burn, emissions, and noise levels. One way to achieve these is to better integrate airframe and propulsion system. Tighter integration, however, may also cause adverse effects to the flow entering the engines, …
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Acoustic optimisation and prediction of sound propagation in turbofan engine ducts
… of noise propagation and<br/>radiation in turbofan engine intakes and bypass ducts, and the optimisation of noise attenuation<br/>by using acoustic liners. A commercial FE/IE code ACTRAN/TM is used<br/>within two shell programs; B-induct for bypass ducts and ANPRORAD for intake …
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Prediction and control of sound propagation in turbofan engine bypass ducts
… liners in the bypass duct of modern turbofan aeroengines. The liners provide the most<br/>effective means with which to suppress the rear fan noise. It is therefore important to make<br/>the best possible use of the available lined area by optimising the liner configuration. A …
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A study of thermographic phosphor thermometry in an operating turbofan engine
… turbine blade metal temperatures in an operating turbofan engine test rig. Thermographic phosphors, ceramics doped with a rare earth metal, were bonded to the turbine blades. These phosphors exhibit fluorescence when optically excited by a laser, and both the intensity and the rate of decay of the …
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A STUDY ON THE PHYSICS OF ICE ACCRETION IN A TURBOFAN ENGINE ENVIRONMENT
Numerous turbofan engine loss of thrust control events have led to a theory that ice is accreting on initially warmer than freezing internal engine hardware and affecting normal operation. The phenomenon is termed ice crystal icing. Previous ice crystal icing research on a simple airfoil …
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Combined Steam Power Cycle and Turbofan Engine for Improvement in Aviation Climate Impacts
… The rate of improvement to aircraft propulsion engines is diminishing and additional improvements often add significant engine cost or weight. With the goal of reducing aviation’s contribution to global climate change, future aircraft engine designers must consider concepts that stray from the …
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A Method to Control Turbofan Engine Starting by Varying Compressor Surge Valve Bleed
… of a study of the starting conditions of a turbofan engine. The research focused on ways to minimize turbine inlet temperature while maintaining an adequate compressor stall margin during engine start by varying the surge valve bleed. Varying the surge valve bleed was also shown to reduce …
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Extension of Particle Image Velocimetry to Full-Scale Turbofan Engine Bypass Duct Flows
Fan system efficiency for modern aircraft engine design is increasing to the point that bypass duct geometry is becoming a significant contributor and could ultimately become a limiting factor. To investigate this, a number of methods are available to provide qualitative and quantitative analysis …
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Design Optimization of the First Stage Fan Blade of a Low Bypass Turbofan Engine
<p>A procedure for solving for and analyzing the aerodynamics, thermodynamics, and blade geometry across the first stage rotor blade under an extreme set of conditions, while altering several design parameters, has been developed and applied. The conditions for which the analyses have been …
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Investigation of Passive Flow Modulation for Full-Scale Air-Oil Coolers for Turbofan Engine Applications
… and improve the fuel efficiency of the engines used for these aircraft. To further improve the efficiency of the turbofan engine research has been focused on the cooling and lubricating system. The thrust specific fuel consumption can be increased if the thrust produced by the bypass is …
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Stereoscopic Particle Image Velocimetry Measurements of Swirl Distortion on a Full-Scale Turbofan Engine Inlet
… the inlet swirl distortion generated by airframe/engine system interactions to identify potential degradation in fan performance and operability in a full-scale, ground testing environment. Efforts are described to address this need by developing and characterizing methods for complex, prescribed …
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Theoretical Modeling with Validation of a Combined HQ-Liner System for Turbofan Engine Noise Control
… is proposed in this work as a device for Turbofan Engine Noise Control. The approach consists of installing circumferential arrays of HQ tubes on the lined sector of the inlet of a turbofan engine. A theoretical model is developed to predict the performance of this system assuming that the …
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Investigation of Inlet Guide Vane Wakes in a F109 Turbofan Engine with and without Flow Control
A series of experiments were conducted in a F109 turbofan engine to investigate the unsteady wake profiles of an Inlet Guide Vane (IGV) at a typical spacing to the downstream fan at subsonic and transonic relative blade velocities. The sharp trailing-edge vanes were designed to produce a wake …
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Methodology Development and Investigation of Turbofan Engine Response to Simultaneous Inlet Total Pressure and Swirl Distortion
As a contribution to advancing turbofan engine ground test technology in support of propulsion system integration in modern conceptual aircraft, a novel inlet distortion generator (ScreenVaneTM) was invented. The device simultaneously reproduces combined inlet total pressure and swirl distortion …
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